Hinged keyboard switch

ABSTRACT

A keyboard switch having a housing for mounting on the conductor of a data processing device with a keyhead hinged to the housing. The housing and keyhead contain cooperating elements of circuit control means actuated by tilting of the keyhead on the housing. The hinge connecting the keyhead to the housing is constructed for assembly without tools. A latch device is provided which will latch the keyhead in depressed position on the housing when the keyhead is pressed downwardly and which will then release the keyhead upon again pressing downwardly on the keyhead.

United States Patent [191 Mehner et a1.

[ HINGED KEYBOARD SWITCH [75] Inventors: Walter Mehner, Schwaig; Werner Tietz, Renzenhof, both of Germany [73] Assignee: DIEHL, Numberg, Germany [22] Filed: Apr. 20, 1973 [21] Appl. N0.: 353,092

[30] Foreign Application Priority Data Apr. 22, 1972 Germany 2219820 [52] US. Cl. .200/338, 200/153 H, 200/159 R, 200/168 G [51] Int. Cl. HOlh 3/04 [58] Field of Search 200/172 A, 61.7, 86.5. 200/153 J, 5 A, 159 R; 340/365 A; 179/90 K [56] References Cited UNITED STATES PATENTS 3/1959 Ehrlich ZOO/86.5 7/1960 Hebert 200/153 .1

[ 1 June 28, 1974 3,353,424 11/1967 Peterson et a1. ZOO/86.5 X 3,588,423 6/1971 Hallerberg. 200/168 G 3,627,935 12/1971 Spierak... 200/5 A X 3,713,670 l/l973 Reynolds 200/168 G Primary Examiner-Robert K. Schaefer Assistant EraminerWilliam .1. Smith Attorney, Agent, or Firm-Walter Becker [57] ABSTRACT A keyboard switch having a housing for mounting on the conductor of a data processing device with a keyhead hinged to the housing. The housing and keyhead contain cooperating elements of circuit control means actuated by tilting of the keyhead on the housing. The hinge connecting the keyhead to the housing is constructed for assembly without tools. A latch device is provided which will latch the keyhead in depressed position on the housing when the keyhead is pressed downwardly and which will then release the keyhead upon again pressing downwardly on the keyhead.

9 Claims, 7 Drawing Figures PATENIEDaunza 1914 3.821534 SHEET 1 OF 4 sis-21.534

PATENTEDJUNZB I974 SHEET 3 [IF 4 HINGED KEYBOARD SWITCH The present invention relates to a keyboard switch for assembly on conductor plates of data processing devices, which comprises a housing provided with centering means for the conductor plate, a spring-loaded keyhead pivotable against the thrust of a spring element, and contact means operable by the keyhead.

An input keyboard system has become known according to which at the bottom side of the keys pushrods are provided for actuating contacts. These keys are pivotally mounted while the bearings of a key line are located below the keys of a preceding key line.

It is an object of the present invention to provide a universally usable keyboard switch of a substantially closed and'flat construction which comprises only a few elements which are easy to produce and to assemble.

It is another object of this invention to provide a keyhead for the keyboard switch system set forth in the preceding paragraph which when operated carries out only a slight tilting movement.

These and other objects and advantages of the invention will appear more clearly from the following specification in connection with the accompanying drawings, in which:

FIG. 1 illustrates a side view of a keyboard switch according to the present invention.

FIG. 2 is a bottom view of the keyhead of FIG. 1.

FIG. 3 shows a top view of the keyboard switch housing of FIG. 1.

FIG. 4 illustrates a top view of a modified housing for a keyboard switch according to the invention.

FIG. 5 is a top view of a keyhead pertaining to the housing of FIG. 4.

FIG. 6 diagrammatically illustrates a keyboard switch according to FIGS. 1 and 4 with a latching or catching mechanism.

FIG. 7 represents a detail of the latching or catching mechanism, of FIG. 6.

The keyboard switch according to the present invention is characterized primarily by bearings which are provided within the region of the upper edge of the rear wall of the housing and into which the keyhead is adapted to be pressed by bearing means likewise provided within the region of the rear wall. To this end, the housing rear wall may be extended in the direction toward the keyhead beyond its upper edge for forming bearing pins, and the rear wall of the keys may have slotted bearing bores into which the bearing pins snap.

The switch according to the present invention may advantageously be produced of injection molded synthetic material. The bearings and abutments for the pivotal keyhead as well as the holding means for the contact elements and for the return springs may be formed as one piece with the keyhead or the housing. The assembly of the housing and keyhead is possible in a simple manner by latching the bearing pins into the bearing bores. The bearings provided on the upper edge of the housing rear wall permit an easy and jamproof operation of the keyhead at a slight inclination only. Furthermore, the housing will assure'a safe and long lasting functioning of the key switch which can be further improved by providing on the keyhead or on the housing a foil which covers up the space between the keyhead and the housing and forms a protection against the entry of dust.

Referring now to the drawings in detail, the keyboard switch illustrated in FIG. 1 comprises a housing 1 and a keyhead 2 pivotally linked thereto. The housing 1 and the keyhead 2 may consist of injection moldable synthetic material. The key switch 1, 2 is connected to a conductor plate 3. For actuating the key, the keyhead is provided with an elevation 4. The keyboard switch has its keyhead 2 extend through a cutout 5 provided in a cover plate 6. As protection against dust, the keyhead 2 has arranged thereon a foil 7 which covers up the space between the housing 1 and the keyhead 2. For centering the location of the housing 1 on the center plate 3, the housing has two pins of which one pin only, namely the pin 8, is visible in a bore 9 of the conductor plate. Furthermore, the bottom 10 of housing 1 and the conductor plate 3 are respectively provided with two bores each for two connecting wires of a contact element as shown in FIG. 3. These bores (in FIG. 1 only bores 11, 12 are shown) are provided within the region of conductor strips 13, 14, a connecting wire 40 being soldered to the conductor strip 13.

As will be seen from FIG. 2, the rear wall 15 of the keyhead 2 has arranged thereon two bearing blocks 19, which are provided with slots 16 having chamfered edges and with bores 17 and 18. Furthermore, the keyhead 2 has an arm 21 with a protrusion 22, with a pin 23 for receiving a return spring 24 and with four supports 25-28 into which latter a permanent magnet 29 may be clamped.

Pins 30, 31 (FIG. 3) which form one piece with the housing 1 are adapted to be snapped into the slotted bores l7, 18 of the bearing blocks 19, 20. The pins 30, 31 are located above the upper edge of housing 1 and outside the housing rear wall 41 so that they are offset in upward direction and in rearward direction in order to obtain a pivot arm as long as possible for the keyhead 2 and thereby a slight tilting inclination only of the keyhead. Furthermore, a cutout 32 in housing 1 is provided for the protrusion 22 of arm 21. The protrusion 22 engages the cutout 32 for limiting the stroke of the key. To secure the position for the spring 24, there is provided a pin 33 which likewise forms one piece with the housing 1 and which, when the key head is assembled, engages the spring 24. In addition to the pin 33, on the bottom 10 there are provided four resilient clamping elements 34-37 which cooperate with each other in pairs. These clamping elements are adapted in a positive and frictional manner to connect a magnetic contact of known type which is mounted in a sleeve 38. The sleeve 38 is equipped with connecting wires 39, 40 which, when the magnetic contact snaps into the latching elements 3437, extends through the bores 11 of the housing bottom 10 and through bores 12 of the conductor plate 3 of FIG. 1 into the range of conductor strips l3, l4 and are soldered thereto.

FIG. 4 shows a housing which in addition to the above described cutout 32 and the latching elements 3437 has two molded-on film hinges 49, with bores 51, 52, these hinges and bores being provided in a rear wall 48 having two cutouts 46, 47. Between the hinges 49, 50 and likewise on the rear wall 48 there is injection molded a leaf-shaped return spring 53 which is laterally defined by the cuts 46, 47, spring 53 being provided with a bore 54.

For fixing the turning point of the hinges 49, 50 as well as of the return spring 53, the hinges and the return spring are provided with notches 5557 at the height of the upper end of the rear wall 48.

The keyhead 44 according to FIG. 5 is, in addition to the elevation 4 referred to above in connection with FIGS. 1 and 2 and the arm 21 with protrusion 22, provided on its rear wall 65 with three cutouts 58-60 in the manner of guiding elements for drawers. Within the region of these cutouts 58-60, a cover plate 31 has three pins 6264 which as to their diameter correspond to the bores 51, 52, 54 of the hinges 49, 50 and return spring 53.

For purposes of assembling the keyhead 44, at the same time the hinges 49, 50 are passed through the cutouts 58, 59 and the return spring 53 is passed through the cutout 60. In this connection the keyhead 44 is slipped onto the hinges until the pins 6264 snap into the bores 51, 52 of the hinges and into the bore 54 of the return spring 53.

The invention is not limited to the specific embodiments discussed so far. Thus, the keyhead and the housing may be formed as one piece by injection molding. Furthermore, with a keyboard switch equipped with a latching mechanism, a lamp may be provided in the interior of the switch, which lamp may advantageously be made of transparent material and which is so connected that the keyhead latched into operating position will be illuminated.

A latching mechanism is shown in FIG. 6 for the keyboard switch of FIGS. 1 and 4. Such latching mechanism comprises a pin 70 which is axially displaceable in a bore 68 of a housing end face 69 and is laterally pivotable. Pin 70 is adapted by a spring yoke 66 to be pressed against a latching path 71 arranged in the arm 21. The spring yoke or spring frame 66 has a U-shape and is clamped into a somewhat undercut recess 72 provided on the upper edge and on the inner side of the housing end side 69.

As will be seen from FIG. 7, pin 70 is, in the starting position of the keyhead 2 shown in FIG. 6, located in a recess provided at the bottom of the latching path 72' and rests with its axially outer end face on a path 73.

Reference to left, right, top, and bottom herebelow refers to the respective directions in the plane of the drawing. With this in mind, path 73 ascends in the lefthand upward direction and is also inclined in the front to back direction so as to decrease in axial depth in the upward direction. The path 73 terminates at the top at a step or corner 75 which is connected by axial surface 83 with an axially facing plane surface 74 which is disposed at a greater axial depth than the upper portion of path 73. Axial surface 83 faces rightwardly and inclines toward the left in the upward direction.

At the lower edge of plane surface 74 there is a downwardly facing step 77 leading axially to an axially facing plane surface 78 located at a lower axial depth than plane surface 74 but at a lesser axial depth than path 76 which is located rightwardly from place surfaces 74 and 78. At the right side, surface 78 terminates in a corner 79 and an axial surface 79' facing toward the right connects corner 79 to path 76.

Path 76, at the lower end, terminates in a corner that is connected by a downwardly facing axial step 80 to the axially deepest and lowermost region of path 73.

Step 80 preferably inclines upwardly toward the left side.

Surrounded by the paths 73 and 76 and the plane surface 78, there is provided an axially protruding latching cam 81 in the recess 72. This cam 81 has a wedged shaped downwardly tapering notch 82 which forms an upwardly facing pin arresting notch and which is connected to step 75 by the inclined rightwardly facing axial surface 83. The notch 82 is closed at the bottom by plane surface 78. The left side of cam 81 guides pin along path 73 during downward movement of keyhead 2.

When the keyhead 2 according to FIG. 6 is pressed downwardly, the spring-loaded pin 70 is guided along the path 73 by step 80 and cam 81, and drops through the intervention of step onto the plane surface 74. During a further downward movement of the keyhead 2, the protrusion 22 of arm 21 pushes against the housing bottom 10. This completes the manual depressing of the keyhead 2. By means of the return spring 24 (FIG. 2; 53 in FIG. 4) the keyhead 2 is tilted back until the pin 70, guided along the inclined axial surface 83, drops over step 77 to the plane surface 78 and moves therealong into the wedge-shaped notch 82. The keyhead 2 isthen held by the spring-urged pin 70 in the switched-on position of switch 38 (FIG. 3).

After a further short depressing of the keyhead 2, the pin 70, which may at this time be guided by step 77, drops over corner 79, and comes to rest on the path 76. As a result thereof, the return spring 24 (FIG. 2; 53 in FIG. 4) will now be able to return the keyhead to its starting position while in the course of this return movement the pin 70 drops over step to the path 73 and comes to a halt in the recess at the bottom of the path thereby stopping the upward movement of keyhead 2.

It is, of course, to be understood that the present invention is, by no means, limited to the particular showing in the drawings, but also comprises any modifications within the scope of the appended claims.

What is claimed is:

1. A switch especially for use as a keyboard switch for assembly on conductor plates of data processing devices, which comprises: a housing having means for connection thereof to a conductor plate and having one of a pair of circuit controlling elements therein, a keyhead having the other of said circuit controlling elements therein, said elements cooperating to control circuit means in response to relative movement of said elements when the keyhead is assembled with said housing, said housing and keyhead each having at least one wall, said walls being in substantially coplanar relation when the keyhead is assembled with said housing portion, detachably interengageable elements of hinge means on the opposed edges of said walls for tilting movement of said keyhead on said housing, spring means acting between said housing and keyhead and biasing said keyhead away from said housing, the said wall of said housing having at least one region extended toward the said wall of the keyhead, said wall of said keyhead having at least one region extending toward the said wall of the housing and said regions being disposed in side by side relation, and a pin in one of said regions and extending laterally into the range of the other of said regions, said other regions having a pin receiving bore therein and a slot parallel to the pin and leading into the bore whereby the pin can be snapped into the bore through the slot in the radial direction.

2. A switch according to claim 1 in which said pin is in the region extending from the wall of the housing and is offset from the plane of the wall toward the outside of the housing.

3. A switch according to claim 1 in which the housing has a bottom wall which on the bottom rests on the conductor plate, the upwardly facing side of said bottom wall comprising upstanding resilient fingers, the circuit controlling element in said housing comprising a component which is snapped into engagement with said fingers from above, said component having wire means connected thereto, and hole means in said bottom wall through which said wire means lead for connection of said component to circuit means.

4. A switch according to claim 1 in which said key head has an arm projecting therefrom on the side opposite the hinged connection of the keyhead to the housing, said arm overlapping the housing and extending from the keyhead in the direction of movement of the keyhead on the housing, said arm having a protrusion on the free end thereof, and said housing being formed with a cutout in which said protrusion is moveable, at least one end of said cutout forming an abutment for engagement by said protrusion to halt said keyhead.

5. A switch especially for use as a keyboard switch for assembly on conductor plates of data processing devices, which comprises: a housing having means for connection thereof to a conductor plate and having one of a pair of circuit controlling elements therein, a keyhead having the other of said circuit controlling elements therein, said elements cooperating to control circuit means in response to relative movement of said elements when the keyhead is assembled with said housing, said housing and keyhead each having at least one wall, said walls being in substantially coplanar relation when the keyhead is assembled with said housing portion, detachably interengageable elements of hinge means on the opposed edges of said walls for tilting movement of said keyhead on said housing, spring means acting between said housing and keyhead and biasing said keyhead away from said housing, said keyhead having an arm projecting therefrom on the side opposite the hinged connection of the keyhead to the housing, said housing having a further wall inside which said arm is disposed, said arm and further wall being in substantially parallel adjacent relation, a latching recess formed in the side of said arm which faces said further wall, and a pin in said further wall extending axially into said recess and spring urged in the axial direction on said further wall, said latching recess and pin cooperating releasably to hold said keyhead in depressed component actuating position on said housing.

6. A switch according to claim 5 in which said one wall of said housing has hinge tabs and a spring leaf flexibly joined thereto and projecting toward said keyhead, slots formed in the said one wall of said keyhead for receiving said tabs and leaf endwise, and means formed on said tabs and leaf and on said keyhead for holding said keyhead in assembled relation with said tabs and leaf.

7. A switch according to claim 5 which includes a flexible dust excluding foil closure member engaging said keyhead at the top and at the bottom engaging said housing and sealing between the keyhead and the housing.

8. A switch according to claim 5 in which said keyhead has a top wall with a downwardly facing underneath side, said circuit controlling element in said keyhead comprising a member on the underneath side of said top wall, and resilient elements dependant from the underneath side of said top wall and supportingly engaging said member.

9. A switch according to claim 6 in which said housing is molded from synthetic material and said tabs and leaf are molded integrally therewith. 

1. A switch especially for use as a keyboard switch for assembly on conductor plates of data processing devices, which comprises: a housing having means for connection thereof to a conductor plate and having one of a pair of circuit controlling elements therein, a keyhead having the other of said circuit controlling elements therein, said elements cooperating to control circuit means in response to relative movement of said elements when the keyhead is assembled with said housing, said housing and keyhead each having at least one wall, said walls being in substantially coplanar relation when the keyhead is assembled with said housing portion, detachably interengageable elements of hinge means on the opposed edges of said walls for tilting movement of said keyhead on said housing, spring means acting between said housing and keyhead and biasing said keyhead away from said housing, the said wall of said housing having at least one region extended toward the said wall of the keyhead, said wall of said keyhead having at least one region extending toward the said wall of the housing and said regions being disposed in side by side relation, and a pin in one of said regions and extending laterally into the range of the other of said regions, said other regions having a pin receiving bore therein and a slot parallel to the pin and leading into the bore whereby the pin can be snapped into the bore through the slot in the radial direction.
 2. A switch according to claim 1 in which said pin is in the region extending from the wall of the housing and is offset from the plane of the wall toward the outside of the housing.
 3. A switch according to claim 1 in which the housing has a bottom wall which on the bottom rests on the conductor plate, the upwardly facing side of said bottom wall comprising upstanding resilient fingers, the circuit controlling element in said housing comprising a component which is snapped into engagement with said fingers from above, said component having wire means connected thereto, and hole means in said bottom wall through which said wire means lead for connection of said component to circuit means.
 4. A switch according to claim 1 in which said keyhead has an arm projecting therefrom on the side opposite the hinged connection of the keyhead to the housing, said arm overlapping the housing and extending from the keyhead in the direction of movement of the keyhead on the housing, said arm having a protrusion on the free end thereof, and said housing being formed with a cutout in which said protrusion is moveable, at least one end of said cutout forming an abutment for engagement by said protrusion to halt said keyhead.
 5. A switch especially for use as a keyboard switch for assembly on conduCtor plates of data processing devices, which comprises: a housing having means for connection thereof to a conductor plate and having one of a pair of circuit controlling elements therein, a keyhead having the other of said circuit controlling elements therein, said elements cooperating to control circuit means in response to relative movement of said elements when the keyhead is assembled with said housing, said housing and keyhead each having at least one wall, said walls being in substantially coplanar relation when the keyhead is assembled with said housing portion, detachably interengageable elements of hinge means on the opposed edges of said walls for tilting movement of said keyhead on said housing, spring means acting between said housing and keyhead and biasing said keyhead away from said housing, said keyhead having an arm projecting therefrom on the side opposite the hinged connection of the keyhead to the housing, said housing having a further wall inside which said arm is disposed, said arm and further wall being in substantially parallel adjacent relation, a latching recess formed in the side of said arm which faces said further wall, and a pin in said further wall extending axially into said recess and spring urged in the axial direction on said further wall, said latching recess and pin cooperating releasably to hold said keyhead in depressed component actuating position on said housing.
 6. A switch according to claim 5 in which said one wall of said housing has hinge tabs and a spring leaf flexibly joined thereto and projecting toward said keyhead, slots formed in the said one wall of said keyhead for receiving said tabs and leaf endwise, and means formed on said tabs and leaf and on said keyhead for holding said keyhead in assembled relation with said tabs and leaf.
 7. A switch according to claim 5 which includes a flexible dust excluding foil closure member engaging said keyhead at the top and at the bottom engaging said housing and sealing between the keyhead and the housing.
 8. A switch according to claim 5 in which said keyhead has a top wall with a downwardly facing underneath side, said circuit controlling element in said keyhead comprising a member on the underneath side of said top wall, and resilient elements dependant from the underneath side of said top wall and supportingly engaging said member.
 9. A switch according to claim 6 in which said housing is molded from synthetic material and said tabs and leaf are molded integrally therewith. 